The director of highways says rises in vehicle duty are needed to make up for a drop in the money it receives from Treasury.
There's to be a further increase from April next year, after Tynwald members last night approved the five per cent hike.
Not all members were keen, though, and some took to their feet to voice their disapproval, saying people were being priced out of vehicle ownership and that motorists were seen as cash cows by governments.
Director of Highways Richard Pearson appeared live on Talking Heads on Manx Radio earlier.
He said vehicle duty raises around £12 million per year, with another million or so raised from elsewhere:
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